Safety razor blade

ABSTRACT

An improved safety razor blade having a cutting edge in the form of a continuous series of substantially sinusoidal micro-waves which provide more cutting surface per unit of length than a smooth- or straight-edged blade and which achieve maximum closeness and comfort of shaving action without angling the blade to the direction of the shaving stroke. The improved blade is adaptable to most of the standard safety razors utilizing either single- or double-edge blades, as well as those of the narrow band or reel type flexible blades. For optimum results, the micro-waves of the cutting edges of the blades are very minute and preferably range in wave depth from crest to trough on the order of between 0.0005 inch minimum depth to about 0.0050 inch maximum depth, and the waves numbering on the order from between about 100 or 200 per inch to about 20 per inch of blade length.

United States Patent Hastings, Sr. Apr. 11, 19 72 54] SAFETY RAZOR BLADEPrimary Examiner-Andrew R. .luhasz 72 Inventor: Donald M. Hastings, Sr.,PO. Box 4088,

Atlanta, Ga. 30302 Attorney-Robb & Robb [57] ABSTRACT An improved safetyrazor blade having a cutting edge in the form of a continuous series ofsubstantially sinusoidal microof the narrow band or reel type flexibleblades. For optimum results, the micro-waves of the cutting edges of theblades are very minute and preferably range in wave depth from crest totrough on the order of between 0.0005 inch minimum depth to about 00050inch maximum depth, and the waves numbering on the order from betweenabout 100 or 200 per inch to about 20 per inch of blade length.

1 Claims, Drawing Figures PATENTEBAPR 1 1 I972 INVENTOR D. M.HASTINGS,Sr.

ATTORNEY) SAFETY RAZOR BLADE The present invention relates to improvedsafety razor blades, and more particularly, to more effective andefficient cutting edges for such blades.

The primary object of the invention is to provide an improved razorblade having a cutting edge which presents a greater effective cuttingedge per unit of length than conventional smooth-edged or straight-edgedblades and which achieves an optimum closeness and comfort of itsshaving action without the necessity of slanting or angling the blade tothe direction of the shaving strokes.

In its preferred embodiment, the cutting edge of my improved razor bladehas the form of a continuous series of substantially sinusoidalmicro-waves consisting of extremely minute scallops. While serrated orscalloped cutting edges have heretofore been utilized in some tonsorialand other cutting implements, the serrations or scallops thereof haveusually been relatively coarse and/or otherwise improperly shaped andhave therefore been unsatisfactory for razor blades as used in shavingthe face. I have found that a commercially feasible and highlysatisfactory shaving action can be achieved by forming the cutting edgeof the razor blade with a continuous series of micro-waves in a criticalrange of between about 100 and 200 per inch but no fewer than about 20per inch of blade length, with the depth of each wave from crest totrough being selected within the critical range of from about 0.0005inch and 0.0050 inch.

A further object of my invention is to provide a safety razor bladehaving an improved cutting edge of the aforementioned type and which canbe utilized for most standard type razors, including those designed forthe newer type narrow blades of the flexible band or reel types.

Other and further objects of my invention will be hereinafter describedor will be apparent from the following description and the accompanyingdrawing and the novel features defined in the appended claims.

In the drawing:

FIG. 1 is a top plan view of a conventional safety razor as equippedwith my improved type of blade;

FIG. 2 is a fragmentary view of the razor of FIG. 1 as primarilydepicted in transverse cross-section and with portions shown inelevation;

FIG. 3 is a plan view of one illustrative double-edged razor bladeembodying my invention.

FIG. 4 is an enlarged fragmentary plan view of the encircled portion ofthe blade of FIG. 3 to better show the micro-waved form of one cuttingedge of the blade;

FIG. 5 is a fragmentary plan view similar to FIG. 4, showing the cuttingedge of the blade on a different enlarged scale and having a cuttingedge of slightly modified form;

FIG. 6 is a perspective view of a so-called flexible band type razorshowing the blade in the form of a narrow band having its cutting edgesconforming to my invention; and

FIG. 7 is a perspective detail view of the unmounted blade of FIG. 6.

Like reference characters designate corresponding parts in the severalfigures of the drawing, wherein I denotes the frame of a conventionalsafety razor having the usual handle 2 extended therefrom. The razor hasthe usual clamping guard 3 for clamping the razor blade 4 between theguard and the frame in the usual manner of such conventional safetyrazors.

In the illustrative embodiment, the blade 4 is shown as being adouble-edged type of blade, but it is to be understood that my inventionis not confined thereto, but is applicable to single-edged blades aswell. My invention is more particularly concerned with the improved formof the cutting edges of the blades, as best seen in FIGS. 3 and 4. Asshown, each cutting edge is generally designated 5 and has the form of acontinuous series of minute scallops 6 as illustrated on an enlargedscale in FIG. 4, said scallops corresponding to microwaves ofsubstantially sinusoidal shape. The cutting edges of the blade arebevelled as customary to give the same the sharpness of cutting actionasrequired for shaving, and because of the micro-waved 'form of thecutting edges, a greater effective cutting length per unit of bladelength than a smooth or straight edge is provided.

I have found that to achieve optimum closeness and comfort of shavingaction, the critical range lies from between and 200 scallops 0rmicro-waves per inch of blade length, to no fewer than 20 per inch,while the critical wave depth from crest to trough, designated as D inthe drawing, ranges between 0.0005 inch and 0.0050 inch. Variouscombinations of these factors can be selected according to thesensitiveness of the facial skin to be shaved, as by classifying theblades in several major classes such as fine, extra fine and superfine", or other appropriate denominations.

Referring to FIGS. 6 and 7, another type of razor blade is illustratedas a flexible narrow band or reel type blade and embodying my improvedscalloped or micro-wave cutting edges, said blade being generallydesignated 4', with the cutting edges being designated 5' and thescallops 6, and conforming to the respective cutting edge features ofFIGS. 1-4 as described above.

While the specific details of my invention have been herein shown anddescribed, the invention is not confined thereto as changes andalterations may be made without departing from the spirit thereof asdefined in the appended claims.

Iclaim:

l. A safety razor blade having a cutting edge of minutely scalloped formand conforming to a continuous and uniform series of sinusoidalmicro-waves all lying wholly in the plane of the flat blade body, withthe troughs between each adjacent pairs of wave crests being of a sizeapproximating the size of an individual human facial hair, said wavesranging in number on the order of between about 100 and 200 per inch ofblade length, and the depth from crest to trough ranging on the order ofbetween 0.0005 inch and 0.0050 inch.

1. A safety razor blade having a cutting edge of minutely scalloped formand conforming to a continuous and uniform series of sinusoidalmicro-waves all lying wholly in the plane of the flat blade body, withthe troughs between each adjacent pairs of wave crests being of a sizeapproximating the size of an individual human facial hair, said wavesranging in number on the order of between about 100 and 200 per inch ofblade length, and the depth from crest to trough ranging on the order ofbetween 0.0005 inch and 0.0050 inch.